Biodigester Construction

Biodigester is a device with a huge sealed container made from bricks and cement. You put the organism such as domestic animal's excrements and left over of vegetables inside, and make compost and biogas with the work of bacteria fermentation. It was integrated into the project to reduce the pollution of the soil and money expenditure due to the excess usage of chemical fertilizer.

The completed biodigester is big like this one. Once the compost is done, it is taken out of the lid that attached at the bottom of the container.

The villagers are putting the organic material for the compost. The capacity of the bin is ten-cubic meter and people had to load the material with a wheelbarrow many times.

There are two more essential material for compost making. One is guts of livestock (in this case, cow). Inside of the guts live bacteria that decomposes organic material. Another is limewater to adjust pH.

You have to wait at least three months after sealing before using compost. The photo to the right is the lid put on the top of the biodigester. The pipe attached to the lid is an outlet of biogas. The gas is usually used for cooking, but we also experimented the power generation using it.